1. Field of the Invention
The present invention is generally related to an actuating mechanism, such as a hydraulic or pneumatic cylinder and, more particularly, to a hydraulic cylinder used to actuate a steering lever of a marine propulsion device in which the cylinder is provided with support members attached to the cylinder's housing structure. The support members are located outboard from the structure to allow external support structures to be located between the cylinder housing and the two support members.
2. Description of the Prior Art
Many different types of hydraulic and pneumatic cylinders are very well known to those skilled in the art and widely used for many actuating applications. The cylinders typically comprise a housing structure with a cylinder bore formed therein. A piston is placed within the bore and is slideable within the bore in response to changes in the relative pressures on the two opposing sides of the piston. A rod is attached to the piston and extends through the cylinder housing at one end of the bore. The rod can be attached to a mechanism that is actuated by the cylinder.
Some type of valve means is normally used to control the flow of a fluid into and out of the cylinder bore at opposite sides of the piston to change its direction of travel. Many different ways have been used to mount the actuating mechanism to a stationary device in order to exert a force, through the rod, between the mounted cylinder housing and a component attached to a distal end of the rod. It is generally recommended that the actuating mechanism be mounted so that resulting forces are contained within the cross-sectional area of the rod so that bending moments can be minimized. This can best be accomplished if the cylinder housing is mounted in such a way that the resulting forces extend through the rod and the point where the cylinder housing is attached to a stationary component.
One problem that exists with known actuating mechanisms of this type occurs when the cylinder housing is used in conjunction with a clevis, as its stationary mounting mechanism, and a severely limited space is available for the cylinder housing to extend in a direction away from the clevis and the rod which is attached to its piston. When mounted on a clevis structure, the cylinder housing is generally of such a size that sufficient space is not available between the clevis ears to provide enough room to allow mounting bolts to be properly used. As a result, known actuating mechanisms of this type are typically mounted with the full length of the cylinder bore extending in one direction from the clevis and the rod extending between the clevis ears and in an opposite direction. Unfortunately, this arrangement requires at least sufficient space at one side of the clevis to extend the full cylinder bore which, in certain applications, is not available.
In view of the above, it would be significantly beneficial if an actuating mechanism could be developed which can be mounted in such a way that the full length of the cylinder bore of the mechanism need not extend in a single direction away from the mounting structure to which it is attached. It would also be highly desirable if this type of mounting mechanism could assure that the forces, resulting from the actuation of the mechanism, pass through the rod of the cylinder and through a line which intersects the points at which the cylinder housing is supported by the external support structure.